Inorganic Chemistry Tools for Bioconjugation, Recognition and Imaging

项目摘要/摘要 我们的实验室对开发新的无机化学工具感兴趣，以满足在 生物结合、识别和成像领域。为了应对这些挑战，新的分子支架 和生物相容性化学是至关重要的。此Mira应用程序的总体目标是进一步推进 仿生硼团簇化学研究领域。这些簇的器官仿生特征源于1)它们的 能够与广泛的取代基进行简单的官能化化学，形成稳定的共价 与星团结合的键--S顶点和2)独特的3D芳香性，使这些星团服从于 显微镜成像的几种模式。在这项工作的范围内还包括一套新的、快速的有机金属 在米拉资助的最初周期中发现的转型，将使人们能够 在生物相关的条件下，合理地系留硼团簇和其他分子。 我们的实验室有兴趣开发新的转型，以模拟操作的简单性 这些硫醇配体通常组装在金属金表面上。这种化学以前已经彻底改变了 我们可以轻松地创建混合贵金属纳米颗粒(例如，硫醇覆盖的金纳米颗粒- AuNPs)。然而，这些杂化的AuNPs并不是原子上精确的，而且配体的日冕是动态的。这些 特征导致杂交车的组成和大小不均匀，最终限制了它们在 抑制蛋白质-生物分子相互作用。为了应对这一挑战，我们开发了有机金属- 基于簇修饰的方法，提供功能生物分子的共价拴系致密电晕 而配体在空间上以三维精度排列。我们建议将这一方法进一步扩大到 快速构建复杂的原子精确的3D纳米分子，用于与各种生物的多价结合 靶标，包括病毒进入受体、生物膜和细胞生长因子。我们还建议 利用开发的金基试剂固有的健壮性和反应动力学 生物分子正电子发射断层扫描(PET)标记。我们还一直致力于开发 新的硼原子簇化学，允许多个反应性官能团在三个- 空间聚集，并使用这些刚性3D物种来标记和锚定生物分子，以实现非常规 折叠和识别。我们提出了能够标记小分子、多肽、蛋白质的化学， 以及具有各种硼簇状支架的细胞，这些支架随后可以用作多价结合剂、亲和力 标签，以及使用拉曼显微镜成像的无荧光标签。最后，我们建议使用 功能化的硼团簇作为相关光学和电子显微镜的双重染色/荧光团试剂 (克莱姆)。具体地说，我们将致力于开发包含重原子官能化的硼团簇的杂化材料 与荧光染料捆绑在一起的染料，这将使特定的细胞细胞器成为靶标，从而 为Clem提供了一种前所未有的光稳定性和无毒剂。

Project Summary/Abstract Our laboratory is interested in developing new inorganic chemistry tools to address unmet needs in the areas of bioconjugation, recognition, and imaging. In order to tackle these challenges, new molecular scaffolds and biocompatible chemistry are crucial. The overall objective of this MIRA application is to further advance the field of organomimetic boron cluster chemistry. Organomimetic features of these clusters arise from 1) their ability to undergo facile functionalization chemistry with a wide array of substituents, forming stable covalent bonds attached to the cluster¢s vertices and 2) unique 3D aromaticity, rendering these clusters amenable for several modes of microscopy imaging. Within the scope of this work is also a set of new, rapid organometallic transformations that were discovered during the original cycle of the MIRA funding that would allow one to rationally tether boron clusters and other molecules under biologically relevant conditions. Our laboratory is interested in developing new transformations that mimic the operational simplicity with which thiol ligands normally assemble onto a metallic gold surface. This chemistry has previously revolutionized the ease with which we can create hybrid noble metal nanoparticles (e.g., thiol capped gold nanoparticles - AuNPs). However, these hybrid AuNPs are not atomically precise, and the ligand corona is dynamic. These features lead to hybrids with a non-uniform composition and size, ultimately limiting their applications for the inhibition of protein-biomolecule interactions. Addressing this challenge, we have developed organometallic- based methods for cluster modification, providing a covalently tethered dense corona of functional biomolecules and ligands spatially arranged with three-dimensional precision. We propose to further expand this approach to rapidly build up sophisticated atomically-precise 3D nanomolecules for multivalent binding to various biological targets, including virus entry receptors, biological membranes, and cellular growth factors. We also propose to utilize the inherent robustness and reaction kinetics associated with the developed Au-based reagents for biomolecular positron-emission tomography (PET) labeling. We have also been engaged in the development of new boron cluster chemistry, allowing for the positioning of multiple reactive functional groups on a three- dimensional cluster and use these rigid 3D species to label and tether biomolecules to achieve unconventional folding and recognition. We propose chemistry that will enable the labeling of small molecules, peptides, proteins, and cells with various boron cluster scaffolds, which can subsequently be used as multivalent binders, affinity tags, and fluorescent-free labels using Raman microscopy imaging. Lastly, we propose the use of perfunctionalized boron clusters as dual staining/fluorophore agents for correlative light and electron microscopy (CLEM). Specifically, we will work on developing hybrids that contain heavy atom perfunctionalized boron cluster stains tethered to a fluorescent dye, which would enable targeting of specific cellular organelles, thereby providing access to an unprecedented class of photostable and non-toxic agents for CLEM.